Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Figure Caption
Osmotic demyelination syndrome usually develops as the sequela of rapid overcorrection of hyponatremia. A spectrum of clinical manifestations, including spastic quadraparesis, pseudobulbar palsy, and locked-in syndrome, are observed, depending on the extent of pontine and extrapontine involvement. Classic MRI features include central, trident-shaped pontine hyperintensity on FLAIR (arrow in A) and T2-weighted sequences, and hypointensity on T1-weighted sequences (B), with sparing of the corticospinal tracts (arrows in B). Postcontrast images usually show absent enhancement, but rarely, peripheral enhancement may be seen acutely. Vasogenic edema could be seen on DWI (arrow in C) in most cases although cytotoxic edema has been reported in some cases.